1. Field of the Invention
The present invention relates to an apparatus for generating water droplets and a method for generating water droplets by trapping water vapor from the atmosphere.
2. Description of Related Art
Due to the influence of CO2 emitted as a result of industrial activities, global environmental temperature has increased in recent years. Plant growing is effective for fixing CO2 thus emitted. Although moisture is essential for plant growing, shortage of water becomes a problem with a rise in the global environmental temperature. In addition, depletion of water also makes it difficult to keep a water resource in urban areas and the like.
A method for generating water droplets from water vapor in the atmosphere is proposed in order to overcome such issues. For example, proposed is a method for preparing a highly viscous liquid by absorbing water vapor from the atmosphere with a deliquescent moisture absorbent (refer to JP-A-2004-181404). Also, proposed is a method for adjusting the temperature of a refrigerant of a refrigeration cycle to a dew point or less by a compressor and thereby cooling the atmosphere to be at a dew point or less to cause dew condensation of water vapor in, the atmosphere (refer to JP-T-2005-518488 and US2007/0039345 corresponding thereto). Moreover, proposed is a method for collecting solar energy to produce an ascending air current and collecting solar energy to produce water vapor from seawater, whereby the air containing water vapor is cooled into water droplets and rain is thus created artificially (refer to JP-A-2007-82408).
According to the constitution disclosed in JP-A-2004-181404, the liquid thus prepared contains the deliquescent material and moisture in the form of a chemically reacted compound so that pure water cannot be obtained. The liquid is therefore not suited for supply to plants or for use as drinking water. According to the constitution disclosed in JP-T-2005-518488, electric energy is required for driving the compressor, which has an adverse effect on reduction of CO2 emissions. According the constitution disclosed in JP-A-2007-82408, large-scale mechanism is necessary for generating water droplets and at the same time, districts, to which the process can be applied, are limited because seawater is required.